The title of the opening story of The Silmarillion (S/15-22), clearly a compound of Ainu “Holy One” and lindalë “music”.
Conceptual Development: Although the story itself dates back to the earliest Lost Tales, this title only emerged in Silmarillion drafts from the 1930s version (LR/156).
The word Ainu is Quenya and is related to words for "holiness" such as aina; the female form (for beings like Melian or Árien, is given as Aini. Supposedly it is derived from the original Valarin word for Ainur which was Ayanûz. They are also referred to as Great Ones or Holy Ones.